The advent of computer networks has proliferated the use of distributed-computing environments. A distributed-computing environment is a type of computing wherein several computer platforms, i.e., different computers, coupled by a network, perform separate but related tasks, (called a process), that are directed in concert toward a single achievement. One example of such a process is the retrieval of all files in a network having the same pattern of letters in the file name. By taking advantage of the computing power of several computers at once, tasks require less time for completion. Use of a processor close to resources to be processed reduces total computing resource requirements.
One method known in the art for practicing a distributed-computing environment is called “remote programming.” In remote programming, a first executing program, called a client process, executing on a first computer system, sends to a second process, called a server process executing on the second computer system, a list of instructions. The instructions are then carried out on the second computer system by the server process, effectuating the goal of the client process. The instructions that the server process is designed to carry out must have some degree of generality, i.e., the instructions must allow some degree of local decision-making with respect to details.
U.S. Pat. No. 6,016,393 to White et al., entitled, “System and Method for Distributed Computation Based upon the Movement, Execution, and Interaction of Processes in a Network”, which is hereby incorporated by reference, disclosed a system that improved upon the concept of remote programming by utilizing processes called mobile agents (sometimes referred to as mobile objects or agent objects). The system described by White et al., provides the ability for an object (the mobile agent object), existing on a first (“host”) computer system, to transplant itself to a second (“remote host”) computer system while preserving its current execution state. The operation of a mobile agent object is described briefly below.
The instructions of the mobile agent object, its preserved execution state, and other objects owned by the mobile agent object are packaged, or “encoded”, to generate a string of data that is configured so that the string of data can be transported by all standard means of communication over a computer network. Once transported to the remote host, the string of data is decoded to generate a computer process, still called the mobile agent object, within the remote host system. The decoded mobile agent object includes those objects encoded as described above and remains in its preserved execution state. The remote host computer system resumes execution of the mobile agent object which is now operating in the remote host environment.
While now operating in the new environment, the instructions of the mobile agent object are executed by the remote host to perform operations of any complexity, including defining, creating, and manipulating data objects and interacting with other remote host computer objects. These interactions may be handled through processes called services. A typical mobile agent object may discover and use services and log the calls to and usage of such services. A system and method directed to the discovery and monitoring of services is disclosed in co-pending U.S. patent application Ser. No. 10/617,604, entitled “SYSTEM AND METHOD FOR THE DISCOVERY OF AND USAGE OF LOCAL RESOURCES BY A MOBILE AGENT OBJECT,” filed on Jul. 11, 2003, which is assigned to Topia Ventures LLC and which is incorporated by reference.
When a mobile agent object is operating in a remote host environment, specific services may be needed but not available within the area of execution of the mobile-agent object called the mobile-agent runtime environment. In such a case, the mobile agent object may be programmed to skip over attempting to use the particular service. In other cases, the mobile agent object may not be programmed with the capacity to determine whether the service is available, thus causing delays and possibly even irretrievable loops. Still other mobile agent objects may be programmed to request the delivery of the service from the original host system for use in the new mobile agent runtime environment.
If the service is requested from the original host system, the purpose of the mobile agent object is defeated in that the mobile agent object is intended to be implanted in a remote host computing environment to eliminate unnecessary communications over the network when data and information are required from the host computing environment. Since the mobile agent object needs to request a service object to be delivered from its original host computing environment to be used in the new mobile-agent runtime environment in the host computer system, communication over the network still occurs and there is no time and computing efficiency realized over the situation where the original host requests the needed data and information directly without using the mobile agent object.
Therefore, a method and system for adding needed services by taking advantage of the mobile agent mechanism wherein communication over the network is minimized is desirable.